Method of making self-lubricating tools



I. B. MOORE.

METHOD OF MAKING SELF LUBRICATING TOOLS. APPLICATION FILED JUNE 3. m9.

Patented Mar. 14, 1922.

UNITED STATES PATENT OFFICE.

METHOD OF MAKING SELF-IQUBRICATING TOOLS.

Application filed June 3,

To all whom it may concern:

Be it known that 1, JOHN B. MooRE, a citizen of the United States, residing at Latrobe, in the county of \Vestmoreland and State of Pennsylvania, have invented a new and useful Method of Making Self-Lubricating Tools, of which the following'is a specification.

This invention is a method of producing tools of the type which is made up of a tool body of high speed metal united to a shank of lower grade metal, and having meciins for, conducting oil to the working en Owing to the excessive cost of high speed steel, it is desirable to utilize metal of a lower grade for the construction of the shank of the tool in order to reduce the cost of manufacture. Heretofore many attempts have been made to produce a tool of this type, which attempts have been more or less successful so far as the initial uniting of the parts is concerned, but the problem of uniting high speed steel to a lower grade metal is a difiicult one and as a consequence tools constructed inthis manner are frequently too weak at the joint to stand up to Working requirements, or else the expense of manufacture is relatively high.

One of the objects of the invention is to provide a tool of the character referred to in which a high speed steel body is united to a shank of lower grade metal, by a process which integrally unites the parts so that they are stronger at their point of union than elsewhere, and having means whereby oil or other lubricant may be conducted to the working end. A further object is to provide a simple process by which a high speed steel body may be united to a lower grade shank and the oil conducting conduits formed without interfering with the uniting of the parts of the tool.

The invention will be hereinafter fully set forth and particularly pointed out in the claims.

In the accompanying drawing Figure 1 is a side elevation illustrating the body of a twist drill of high speed steel, before the same has been twisted and united to the shank. Figure 2 is a side view illustrating a completed drill constructed in accordance with the invention. Figure 3 is a longitudinal sectional view illustrating the joint of the completed tool. Figure 4 18 a similar view illustrating the joint after the Specification of Letters Patent.

Patented Mar. 14, 1922.

1919. Serial No. 301,438. 1

parts have been united and before completion of the oil conduits. Figure 5 is a transverse sectional view illustrating the joint of the completed tool, taken on the line 55, Figure 3.

Referring to the drawing, 10 designates the high speed steel body of atool, which may be of any desired type, that illustrated in the drawings being a common form of twist drill blank provided'with spaced apart longitudinal bores 11 which extend entirely through the length of the body, and are united at the shank end 12- by laterally disposed bores 13, which converge to the center of the tool body. A twist drill has been selected for illustrative purposes but it is to be understood that the invention is not limited to this particular type of tool, but may be applied to any tool in which a member of high grade metal is attached to a member of lower grade metal and provided with lubricating channels. The shank end of the tool blank is tapered as shown. In practice, the blank is formed and provided with the bores, after which the body is twisted to the form illustrated'in Figure 2 and the tapered shank end is provided with screw threads 14, or transverse shoulders of any other desired form, compleinental to the inner wall of a socket 15 formed on the shank 16. The tool and the shank may be united in any suitable manner but it is preferred to employ the method described and claimed in Letters Patent 1,191,717 granted July 18, 1916, in which the threads of the tool body are engaged with complemental threads of the shank socket, and the spaces between these members is filled by a suitable brazing material 17, which flows into the screw threads, thereby insuring a perfect, integral joint.

Before uniting the body 10 with the shank 16, the shank ends of the bores 11 are permanently closed by plugs 18 of any suitable material, and the meeting ends of the bores 13 are similarly plugged, as indicated at 19. After the plugs are applied, the tool body and the shank are united, as above described, it being understood that the shank has previously been provided with a bore 20 extending almost through to the socket. After the tool body and shank have been united, the wall between the bore 20 and the socket 15, and the plug 18, are removed by means of a suitable tool, thereby providing a continuous conduit through the bore 20, bores 13 and bores 11 to the point of the tool. The completed tool is then ground, polished and finished in the usual way.

' Having thus explained the natureof the invention, and described an operative manner of constructing the same, although withapart longitudinal bores, connecting said bores by shorter bores leading in from a common point at the shank end of the tool, plugging all ofsaid bores at the shank'end, inserting the plugged end into the socket of a shank and permanently uniting the parts,- and finally boring through the shank and the plug which fills the shorter bores.

2. A method'of producing tools comprising providing a tool body with spaced apart longitudinal bores, connecting said bores by shorter bores converging to a 7 common point at the shank end of the tool body, plugging all of said bores at the shank end, inserting the shank end into the socket of a shank and permanently uniting the parts, and finally boring longitudinally through the shank and through the plug which closes the converging bores.

3. A method of producing tools compris ing providing a tool body with spaced apart longitudinal bores, connecting said bores by shorter bores converging to a common point at the shank end of the body,

plugging said longitudinal bores at the shank end and also plugging the converging bores "at their point of meeting, inserting the shank end of the body into the socket ot a shank having a bore separated from said socket by a solid wall, and permanently uniting. the parts, and finally boring longitudinally through the closed Wall of the shank and through the plug which closes the converging bores, to establish communication between the bore of the shank and the bores of the tool body.

LA method of making self-lubricating tools comprising providing a tool body with spaced-apart bores connected with each other at one end of the tool, permanently uniting the last mentioned end of'said'tool body with a shank, and finally providing a longitudinal opening in saidshank communicating with said bores at their point of connection.

5. A method of making self-lubricating tools comprising providing a tool body with spece'd-apart bores connected with each other at one'end of the tool, providing a shank with a longitudinal bore and a socket, said bore being closed alt-the socket end, uniting one end of the tool'body with the socket portionof said shank, and finally forming an opening in the socket end of the bore of'the' shankin register with the point of connection of the bores of the tool body. w 5 r r In testimony whereof I have hereunto set my hand.

JOHN nfMoonn} 

